Sunday, March 11, 2012

Troubled Waters - Distress Signals

Another endangered species?
So far we have mostly looked at the direct effects on fish and the fishing industry. Even in remote places such as the west coast of Western Australia or the most southerly fishery in Australia, I hear the same complaint: that the fishing industry is no longer viable for small fishing enterprises like these. Despite this, there are still 35 million people in 20 million boats ploughing the oceans in search of fish.

But its not just the fish or the fishing industry. Every day there are new groups or individuals raising the alarm about this maritime creature or that  -from seahorses in Malaysia to sea lions in Chile, from sea turtles  in Indonesia to the Gulf of Mexico and Cap Verde in Africa, to polar bears and seals in Alaska. Those which are not dying directly as a result of destructive fishing practices, or because they are competing for diminishing supplies of food, are dying because of enormous changes in their habitat. Apart from those reasons already mentioned in the case of fish, new ones are constantly emerging. For Arctic marine species such as the polar bear, the ground is literally disappearing beneath their feet as the polar ice shrinks. It has retreated by 75% over the last 30 years. Over 1000 a year are also shot by hunters in the five countries where they still exist. In the Antarctic, warmer waters are enabling subtropical predators to travel further south, thereby threatening existing species.

You will also notice a lot of petitions about sharks, either about creating reserves to protect them or to ban shark finning. Rising affluence in China is leading to huge demand for shark fin soup which is considered a delicacy. This means 700 million sharks are being killed annually and often cruelly and wastefully, just for their fins which is helping to drive some species to extinction. Many states have already made shark finning illegal, but do not do enough to enforce it. Some such as the USA, Columbia, and Costa Rica insist that sharks must be landed with their fins intact, while still others such as the Maldives and Honduras have gone further by establishing shark sanctuaries.  Should additional reasons be required for ending this custom, it has been found that sharks, being at the top of the food chain, concentrate high levels of mercury and that the fins themselves contain a neurotoxin which is implicated in brain disease.

 As sharks are the top predator in most regions, this creates imbalances in the food chain, allowing some species to thrive at the expense of others. This also occurs with transcontinental shipping which allows accidental introductions of new species into regions where they have no natural enemies. A case in point are the plagues of  starfish  which we now have in Tasmania. The Northern Pacific Seastar which is thought to have arrived in the ballast water of visiting ships is taking over intertidal zones and driving out more desirable species such as shellfish.

While we are by now almost accustomed to the horrifying sight of oiled seabirds and blackened beaches as a result of the breakup of ships - and they do not have to be oil tankers, there are also more insidious forms of marine pollution which attract little attention until beaches are closed to swimmers or mystery ailments appear in farmed oyster stocks. It has been estimated that there are now four hundred  "dead zones " around the world -places in the sea where no marine life exists, usually at the deltas of major rivers and off the coast of large cities, some of the largest of them being in the Baltic Sea, the Gulf of Thailand, at the mouth of the Yellow River and in the Gulf of Mexico. 

While point sources of pollution are usually easily identified, the dead zones are usually the cumulative effect of multiple sources - e.g. fertiliser and chemical run -off from farms, chemicals from industrial processes, sewerage, droplets of oil and rubber carried in storm water from roads and the detergent from thousands of sinks. Even soil from farms or from land clearing or flooding can become a pollutant and, as the US National Atmospheric and Oceanographic Administration (NOAA) points out so can particulates in the atmosphere.For an interesting picture of how air pollution carries across the ocean from Asia see this article  in the Discovery News.
As a biologist remarked while I, along with hundreds of other volunteers was helping to wash penguins  after ship ran aground in Tasmania's coastal waters. "Where were all these people when the pilchards died?"  It's true that we are much more moved by the plight of large furry animals, but the reality is that if  the base of the food chain is being lost due to pollution - the molluscs, the plankton or the smaller fish, then the larger species will suffer, no matter how much we try to save them.


Solid Rubbish 
Another contributor to the dead zones is solid rubbish. Solid rubbish also affects marine life both directly, as when seabirds, fish, turtles and mammals, drown after being caught or injured by nets, lost fishing tackle and debris, or because of rubbish discarded from the land and lost from ships, but also indirectly because of disruption to their endocrine systems believed to be caused by the ingestion of plastics.  
 According to a respondent in Donovan Hohn's Moby Duck (p. 24) thousands of shipping containers are washed overboard every year e.g. in January 2000, “it was 26,000 Nike Sandals, another 10,000 children's shoes and 3,000 computer monitors." He also mentions the surprising number of cargo ships lost - approximately two a week. Most of the rubbish however, about 80% of it according to a 2004 report, originates on land. While some of these tragedies may not be preventable, there are many that are.

 For example, banning the use of plastic bags, ring tops and six pack rings, disposable takeaway containers and drink bottles or at least putting deposit legislation on these, would greatly reduce the amount of rubbish entering our waterways and ultimately the sea. We now have not only the Great Pacific Garbage Patch which covers an area the size of Texas, but five other similar ones where ocean currents converge. In a bit of poetic justice for air pollution travelling eastwards across the ocean to America, plastic rubbish originating in the USA has been found washing up on beaches in China. 
I tell a lie. I have just read an article that says, the Great Pacific Garbage Patch is 'only' twice the size of Texas. Read More ...

Another Preventable Tragedy? 

I have just been reading about the disproportionate amount of rubbish and pollution produced by cruise ships which have just won the "Dinosaur of the Year Award" for amongst other things, failing to properly dispose of their rubbish, effluent and waste water. Read more....

Noise  Pollution

Also of concern is the amount of noise now being made in the ocean. Noise travels a long way under water and it has been doubling every decade for 60 years. It has long been thought that this is responsible for the many strandings of whales and dolphins around the world, but I have just read some research which found that it also affects things like lobster, shellfish and shrimp and causes enough stress in these and  other marine species, especially those which rely on sound, to affect their reproduction. Read more ...

It is no longer a question of just saving the Whale. We have to try to save everything. I know that we can't simply stop everything at once, but could we please at least stop the most destructive practices and the most unnecessary. If we cannot curb our voracious appetite for fish – there are several guides which show which ones have been caught sustainably – on the Greenpeace UK site for Europeans and a new listing of sustainably caught tuna on their Australian one. We must also do our best to eliminate those practices which lead to more species becoming extinct, including better regulation and policing of those regulations when and where they exist.  I hate to use what has become a cliche but you have to agree with the words attributed to chief Seattle.

“Only When the Last Fish has gone, will we realise that we cannot eat Money.”

These are just some of many petitions


Albatross in SOUTH AFRICA
Beluga Whales in ALASKA, Keep Whale protection
Beluga Whales in ALASKA and Mining
Whaling and Dolphins - Keep the Ban on and include Dolphins, UN
Ban Dolphins in Captivity, NORTH ATLANTIC
Dolphins End capture, JAPAN Capitivity Everywhere
Dolphins JAPAN
Blue Fin Tuna - Create a Marine Sanctuary, SPAIN
Sea Turtles BALI and INDONESIA - AFRICA
Sea Turtles, KENYA
Sea Turtles Gulf of Mexico  


Sharks

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